Beta-{8 benzo(b) thienyl-3{9 -alpha-allyl-propionic acid esters

ABSTRACT

Beta -(Benzo(b)thienyl-3) propionic acid derivatives in the form of their amino esters (and salts thereof) are prepared. These compounds have spasmolytic, vasodilatatric, antiserotonic and local anaesthetic activity.

United States Patent [191 Robba et al.

[ ]l Feb. 11, 1975 BETA-[BENZO( B) TlllENYL-3l-ALPHA-ALLYL-PROPIONIC AClD ESTERS Inventors: Max Fernand Robba, Paris; Denise Jeanne Claude Duval, Yvelines.

both of France Assignee: lnnothera, Val de Marne, France Filed: June 7, 1971 Appl. No.: 150,747

Foreign Application Priority Data June 12, 1970 France 70.21679 US. Cl... 260/330.5, 260/247.1 P, 260/293.57, 260/326.34, 424/275 lnt. Cl C07d 63/18 Field of Search 260/3305, 247.], 326.3, 260/29368, 293.57. 326.34

Primary Examiner-Donald G. Daus Assistant Examiner-Jose Tovar Attorney, Agent, or Firm-Stevens. Davis, Miller & Mosher [57] ABSTRACT B-[Benzo(b)thienyI-3lpropionic acid derivatives in the form of their amino esters (and salts thereof) 'are prepared. These compounds have spasmolytic, vasodilatatri'c, antiserotonic and local anaesthetic activity.

4 Claims, No Drawings 1 BETA-l BENZO(B THIENYL-3]-ALPHA-ALLYL-PROPIONIC ACID ESTERS g l l -CH -CEI-COOR" wherein R represents an allyl, phenyl, benzyl, thenyl, tetrahydrofurfuryl or tetrahydropyrannyl-methyl radical and R represents a hydrogen atom or the group wherein R represents a hydrogen atom or a linear or branched alkyl having l to 3 carbon atoms Am represents the radical ofa dialkylamine of which the alkyls have 1 to 4 carbon atoms or the radical of an cyclic amine having 5, 6 or 7 members which may include a supplementary hetero atom, and

n is l or 2.

The cyclic amine radical may be particularly that of pyrrolidine, piperidine, cyclohexamethylene-imine or morpholine.

The invention includes the salts which give aminoesters with pharmaceutically acceptable mineral or organic acids as well as the quaternary ammonium derivatives of these amino-esters, and the racemic and optically active forms of the acids and amino-esters.

The derivatives of B[benzo(b)thienyl-3] propionic acid may be prepared, according to the invention, from 3-chloromethyl-benzo(b) thiophene by malonic synthesis.

One may work, in particular, in the following manner: the 3-chloromethyl-benzo (b) thiophene is condensed with a malonic ester carrying, in 2-position, the

radical R (compound 11]) by warming to reflux in ethanol in the presence of sodium ethylate.

After hydrolysis in an aqueous hydrochloric acid medium there is obtained a malonic ester carrying in 2- position, as well as the radical R, the radical [benzo(b) thienyl-3] methyl (compound N) which is extracted with diethyl ether and distilled.

By prolonged heating under reflux in a solution of potassium in benzyl alcohol, the malonic esters (IV) are saponified and decarboxylated. After dilution with water and acidification, there are obtained the ,B-[ben- 20(b)thienyl-3] propionic acids (Compounds l) which may be purified by distillation in vacuo and recrystallisation.

The malonic ester used is, for preference, ethyl malonate.

in this case the reaction scheme is the following:

COOC H cues a 25 till-C a co a klvz 5 The aminated esters (compounds 1]) of thefi-[benzo(b) thienyl-3]propionic acids (compounds I) may be prepared by heating the acids to reflux in isopropanol with the amino-alcohol chlorides of the formula Cl-CH-(CH2),.A

, wherein R n and Am have the meanings given above.

EXAMPLE I a. Allyl [benzo(b) ethyl ester A solution of 23 g of sodium and 200 g of Z-allyl malonate ethyl ester in 600 cc of absolute ethanol is heated to reflux for 1 hour. It is :slightly cooled and a solution of l8l.5 g of 3-chloromethyl-benzothiophene in cc of absolute alcohol is poured in. It is heated to reflux, with stirring, for 17 hours. lt is poured into 1 litre of water, acidified with hydrochloric acid and extracted with ether. It is dried over sodium sulphate, the solvent eliminated and it is distilled in vacuo. A yellow thienyl-3) methyl]malonate poured into 2 litres of water, acidified with hydrochloric acid and extracted with benzene. It is dried over sodium sulphate, the solvent eliminated and the residue distilled in vacuo. A yellow oil is obtained. B.pt. 215. Yield 80 percent.

EXAMPLES 2-6 a. By operating asin Example 1 (a) one obtains in the form of yellow distillable oils the malonic esters indicated below:

phenyl [(benzo(b) thienyl-3 )-methy1] malonate ethyl ester, B.pt. =235245-Yield:72 percent benzyll(benzo(b)thieny1-3)-methyl] malonate ethyl ester, B.pt. =250260-Yield:75 percent (thieny1-2' )[(benzo( b)thienyl-3 )-methyl]malonate ethyl ester, B.pt. =280290-Yield: 80 percent (tetrahydro-furfuryl)[(benzo(b)thienyl-3')-methyl] malonate ethyl ester, B.pt. =238-246-Yie1d:80

percent (tetrahydropyrannyl-methyl) [(benzo(b)thieny1-3)- methyl] malonate ethyl ester-B.pt. -,=247-253- Yield: percent.

b. From the listed malonic esters, and operating as in Example 1(b) there are obtained the following B-lben- 20(b) thienyl-3] propionic acids in the form of distillable oils or solids:

a-phenyl [3-[benzo(b)thienyl-3] propionic acid;

white crystals; m.p 120 B.p,,=260263; cristallisable in a mixture of 1/1 acetonitrile and hexane- Yield: percent. u-benzyl B-[benzo(b)thienyl-3] propionic acid;

white solid m.p. 1 16; B.p. =245-25 5; cristallisable in a mixture'of 2"litres of hexane and 150 cc of ethyl acetate -Yield: percent.

a-(thieny1-2)B-[benzo(b)thienyl-3] propionic acid;

white crystals; m.p. b.p. =29O3OO; cristallisable in a mixture (4/1 of hexane and ethyl acetate- Yield:75 percent.

a-tetrahydrofurfuryl B-[benzo (b) thieny1-3] propionic acid; white crystals; m.p. 1 16; b.p. =240243; cristallisable in a mixture (4/1) of hexane and ethyl acetate-Yield :80 percent.

a-(tetrahydropyrannyl-methyl)B-[benzo (b) thienyl- 3] propionic acid; white crystals; m.p. cristallisable in a mixture of (1/2) of ethyl acetate and hexane-YieldzSO percent.

EXAMPLE 7 N,N-diethylamino ethyl ester of a-phenyl-B-[benzo (b) thienyl-3] propionic acid and its oxalate There is heated to reflux for 17 hours a solution of 5 g of a-phenyl-B-[benzo (b) thieny1-3]propionic acid and 2.4 g of N,N-diethylamino-chloroethane in 60 cc isopropanol. 1t is evaporated to dryness in vacuo, the residue taken up in a saturated aqueous solution of sodium carbonate and extracted with chloroform. The solvent is dried over sodium sulphate and then eliminated. The residue is dissolved in 50 cc acetone, the solution is filtered and then added to a solution of 3 g oxalic acid in 20 cc acetone. It is heated to reflux for 30 minutes and separated after cooling. It is recrystallised in a mixture of 1/1 diethyl ether and absolute ethanol. White crystals are obtained. M.p.

Yield 65 percent.

In Tables 1, 11, 111, IV and V set out below there are identified the amino ester salts of B-[benzo(b) thienyl- 3] propionic acids prepared in a similar fashion, the salt of Example 7 being assigned the number 13.

Table 1 1 n0. R'- acidic of the Stiltiielting Yield Solvent of 3 forming acid HY Point 00- f. criatnllisn Lion (cii -N( citric acid 97 60 acetonitrile c 11 l 2 (ca -n\ oxalic acid 98 65 acetonitrile l 3 (ca -z-r citric acid 85 75 acetonitrile 4 (ca -u ,0 oxalic acid no 70 acetonitrile l 5 pi i oxalic acid 12 65 nc tonitrilo Table l-Continued No. Nature of the salt- Helting Yield Solvent of forming abid H! Point criatallisation 6 (cs 44 3 oxalic acid 115 acetonitrile 1 3 cc .c- .ca l.-. ..c a.. l c

- c P 7 H 2H5 2 3 H citric acid a5 acetonitrile (l) 2 5 plus ethyl ether (1) c a 1 a (CiI -N\ I itric acid .86 acetonit'rile M ...y 9 ((211 n oxalic acid 102 65 acctoniirilc 1 1O '(CH2)3-IT oxalic acid 6o nc etonit'rile (l) I plus ethyl other 'I A (1) I I l1 -cu-ca #1: oxalic acid 92 65 cetonitrile l 2 \j CH I Tablp ll s T -cr! *d coo a! 210. micro of the salt ldoliinc Yield Solvent of forming acid HY Point 0 cristnllisrition (CH -N 3 oxalic acid 150 70 acetonitrile (l) C11 plus ethyl ether (1} 15 (CH2)2-N 2 5 oxalic acid I 65 absolute ethanol C2H5 (1) plus ethyl a Wi h r l4 (CH2)2-J citric acid 85 65 acetonitrlle 15 (CH2)2-N oxalic acid 70 absolute ethanol (1) plus ethyl fih iKU 1r, (Cii --N oxal c acid 75 ethyl alcohol osas l7 ((21 oxalic acid 70 absolute ethanol (1) plus ethyl ether (1) WM 3 m (CH -N oxalic acid 168 60 absolute cthaoolu) CH3 plus ethyl ether (1) Table ll-Continugd No. 'R' Nature of the salt Melting Yield Solvent of forming acid my Point criatnllisation c 19 (CH2)3-N 2H5 citric acid I 95 65 acetonitrile PO (CH2)3-N oxalic acid 103 65 I abuolute ethanpl (1) plus ethyl ether (1) 21 (cu -N oxalic acid a 141 70 ethyl alcohol 95 (1) plus ethyl I ethgr (l) 22 (CH2)3-N M oxalic acid 101 65 acetonitrile 23 -CH-CH2-N' citric acid 90 70 acetonitrile (1) I ulus ethyl ether ca (1) I:

Table m cd I Iio. R' li-zture of the salt Z-.elting Yield Solv nt of forming acid HY Point 0 cristallisation .011 P4 (c11 -1:' oxalic acid 133 v 75 ucetonitrile (1) CH ethyl ether' 1 25 (cu -n citric acid 115 70 acetonitrile 1.. M9 26 (CH -N citric acid 100 acetonitrile 2 2 i- (cH \I citric acid 85 I acetonitrile;

a g 28 (CH2)2-N oxalic acid 136 ncetonitrile i 29 (c11 11 oxalic acid 118 ucetonitrile 0 11' g 30 (ca -n citric acid 87 acetonitrile i a a 2 5 8 ("1 i 31 (CH2)3-N oxalic acid 113 75 acetonitrile (l) i ethyl ether (1) Table in Continued No. Nature of the ccitr-zci ic Yi m Solvent of.

forming acid HY Point fcristnllisntion 2 (059 41 citric acid s5 70 acetonitrile (1) ethyl etncr (1) 33 (CH Tv' oxalic acid 128 75 acetonitrile (l) 2 3 ethyl ether (1) F i 34 cn-cn -N citric acid 80 65 acetonitrile 2 5 cu 3 M.

Tamil! -'/\/S\ f.

\/ \UE2 (Z-i one -R'-; HY

cn S

. lvent of No, R! Nature of me salt he ting Yield .F i forming ccid HY Point z: 1 CII 35. (CH2)2 3 01ml ic acid 133 7 70 acetonitrile i C113 c H v j 36 (CH2)2-N 2 5 citric acid 111 75 nc tonitrile (1) c ethyl ether (1) 2K5 537 (cm -1: I citric acid 105 70 ncetonitrile (1) 2 2 ethyl ether (1) 38 (CH2)2-N citric acid 88 a0 acewnitrile thyl ether (1) 59 (021 o oxalic acid 160 acctonitrile (1) l ethyl ether (1) 40 (CH2)2-N/\/ oxalic acid 133 absolute ethanol 1; ethyl ether 1 cm mm :'41 (on -N/ 3 oxalic acid 115 70 acetonitrile 1' 2 3 \CH f. 1 3.1...-1 c 1-- c w 1 1 c H c 42 (ca -n 2 5 citric acid 1 a5 nc tonitrile 2 5 c .c 43 citric acid 85 acetonitrile (1) (CH -N I ethyl ether (1) Table lV-Cminucd No. 'R' Nature of the salt "lzcitin Yield Solvent of forming acid a l Point 0 risto l cctioc 44 (Cfl -N oxalic acid 135 75 absolute ethanol 21) vthyl ether l) (cfl -N citric acid 86 acetonitrile 46 CH-CH2- citric acid 78 ncetonitrile l i I Tb'fl 4:1: coo 'R' KY Ho. Nature of the salt Z-Lelting Yicld Solvent of l Q forming acid HY Point 0 7b cristallisrition i 05 l 547 (CH2)2-1-' oxalic acid 11o acetonitrile on 1 2 5 jde (cl -N citric acid 7s wetomtrlle (1) 0 ethyl ether'kl) 549 (CH2)2-N\' oxalic acid 75I acetonitrile :50 (CIi -H oxalic ncid 70 absolutqnthanol 5 (l) tliyl e tner (l) 5\ (CHQZ-IK oxalic acid 124 75 acetonitrile I 3 52 (CH2)3-N oxalic acid 89 65 c zlceconitrile 0 "d 53 (C1i -N Z 5 citric acid 83 75 ricetonitrile zfs 54 (CH2)3-1\' I oxalic acid 100 70 acetonitrile 55 (CH2)3-N: oxalic acid. 95 75 ncetonitrile 56 (cn oxalic acid 95 70 acetonitrile The salts of amino ester derivatives of B-[benzo(b) thienyl-3 propionic acid have been made the subject of a pharmacological study showing their spasmolytic, Vasodilatatric, antiserotinic and local anaesthetic activity.

1. Acute Toxicity The acute toxicity of the amino ester derivatives of B-[benzo(b) thienyI-3] propionic acid have been studied in the mouse by intraperitoneal and oral routes, the products being administered in an isotonic solution of sodium chloride, 0.9 percent, or in suspension in a dilute aqueous solution of carboxymethyl cellulose.

The calculation of the DL50 has been effected according to the method of MILLER and TAINTER (MlLLER. L. C., TAINTER M. L.-Proc. Soc. Exptl. Biol. Med. 1944-57-261,264).

The results obtained are set out in Table IV for the compounds used by way of example.

TABLE VI Acute toxicity in the mouse Compound Route Cone. g/100 ml DL 50 (in mg/kg) No. of solution or suspension i.p. 1.0 150 i 17 6 i.p. 1.0 about 120 i.p. 2.0 210 i 7 v.0. 5.0 1290 t 80 11 i.p. 1.0 270 i- 59 y 37 i.p. 2.0 320 t 21 42 i.p. 2.0 240 i 18 43 i.p. 1.0 160 z n i.p. 2.0 140 t 9 49 v.0. 5.0 about 650 50 i.p. 1.0 122 i 12 51 i.p. 1.0 121x10 i.p. 1.0 145 1: 9 53 v.0. 5.0 1150 t 78 i.p. 1.0 100 t 12 54 v.0. 5.0 400 i 27 i.p. 1.0 85 x 12 55 v.o. 2.5 about 450 lated rat duodenum.

The average activity of the substances studied has been effected by determining graphically their DE 30 and DE 50 these being expressed in pg for ml of .bath.

The results obtained with certain selected compounds taken by way of example and indicated in Table Vll show that the derivatives of B-[benzo(B)thienyl-3] propionic acid possess a spasmolytic activity of papaverinic type.

This activity is equal or clearly superior to that of papaverine hydrochloride, this reference substance having a DE 50 varying generally between 60 and 80 ug/ZO 'ml of bath in the experimental conditions defined above.

b. To show activity of atropinic type the contracturant used is acetylcholine chloride acting onthe isolated ileum of the guinea-pig.

The average activity of the substances studied has been similarly researched by determining graphically their DE 30 and DE 50, these being expressed in lg/20 ml of bath.

The results obtained with certain compounds selected by way of example and indicated in Table VI] show that the derivatives studied posses a weak atropinic activity, the DE 50 of atropine sulphate being equal to or less than 0. l pig/2O ml. of bath in the experimental conditions defined above.

TABLE VII Spasmolytic activity in vitro Spasmolytic activity Compound Papavernic type Atropinic type DE 30 DE 50 DE 30 DE 50 3. Vasodilatatric activity a. The vaso-dialtatric activity with regard to the muscle fibre of vessels has been shown on the perfused isolated ear of the rabbit, after catheterism of the median artery, with the aid of a Tyrode solution maintained at ambient temperature.

The fall is registered with the aid of electronic apparatus including a Fleisch totalisator, the Tyrode solution being recovered at the ends of the efferent" veins It diminishes if one adds to the perfusion liquid a sub stance possessing vaso-constrictive properties such as less marked according to the concentration used.

There has been observed for certain on these derivatives, a vaso-dilatatric activity which, compared to that of papaverine hydrochloride, is of a similar intensity.

b. The vaso-dilatatric activity with regard to the coronary vessels has been shown on the isolated heart of the guinea-pig perfused according to the classic, technique of LANGENDORFF, the coronary reduction being registered with the aid of electronic paratus including a Fleisch totalisator.

There has been observed for certain derivatives selected by way of example a vaso-dilatatric activity comparable to that of papaverine hydrochloride. These derivatives equally oppose the vase-constriction due to barium chloride added to the perfusion liquid.

4. Anti-serotonic activity This has been researched in the rat by the technique of the acute oedema localised in the metatarsal region, provoked by the injection of 0.05 ml of a 0.01 percent solution of serotonine (sulphate of 5-hydroxy-tryptamine-creatinine) in an isotonic solution of sodium chloride.

The plethysmometric measurements of the paw having been subjected to the injection have been effected before, and at different times after, the injection of the serotonine.

The different results obtained with certain derivatives selected by way of example are presented in Table V111 and show a clear inhibition of the acute oedema localised consecutive to the intraplant injection of serotonine.

The method of MOUKHTAR has been chosen to show the activity of the derivatives studied on conduction anaesthesia (A. MOUKHTAR, C.R. Soc Biol.

The reference local anaesthetic substance used in the tests has in each case been procaine hydrochloride in 0.5 percent solution in an 0.9 percent isotonic solution of NaCl. The three concentrations used to study the local anaesthetic activity ofthe new derivatives are 0.50, 0.25 and 0.10 percent, the'vehicle being the isotonic 0.9 percent solution of NaCl.

The average anaesthetic activity of the substances chosen is expressed comparatively to that of the reference product chosen, by calculating the ratio of the average number n of the stimulations necessary to obtain the appearance of the skin reflex in the case of the de rivatives studied, to the average number (n) of the stimulation determined for the reference substance.

For example, in the experimental conditions defined above a substance possessing a local anaesthetic activity expressed by the number 1 has an activity equal to that of procaine hydrochloride.

The results obtained with certain selected compounds, by way of example, are indicated in Table IX and show a local anaesthetic activity comparable to that of procaine hydrochloride.

TABLE IX The procaine hydrochloride and the derivatives studied are administered by the intradermal route at the rate of 0.20 ml per injection.

local concentration in average number of annesthetic g/ 100 ml stimulations activity Comof the derivof procaine for the for procaine pound No. ative studied hydrochloride derivahydrochloride tive studied it n' TABLE Vlll The derivatives of B-[benzo(b)thienyl-3]-propionic The derivatives to be studied have been administered acid can used in human therapy and in veterinary by the oral route 30 minutes before the serotonine. 55 thefapy by f of their spasmolytic* vasodilatatric' antiserotonmic and local anaesthetic properties.

The compounds which are particularly interesting in Compound No. Dose in Cone. average percentage thls regard are compounds 1 mg/kg /100 ml reducflon jngedema 32, 37, 46, 49, 50, 51, 53, 54, and of Tables I to 9 lb 1 g-h The new drugs may be utilised in the treatment of 1 9" spasmodic and painful conditions by digestive, biliary 7 50 05 36.6 and urinary routes, of the arterio-venous system and g; 38 8-; J :3: the pelvic organs and in insufficient peripheral coro- 50 nary and cerebral circulations. 54 g? "gig 1 28 5 The new derivatives may be presented for adminis- 30 3 tration by oral, rectal or parenteral routes in man or an- 55 0.5 40.7 39.8 lmals, notably in association with excipients appropri- 5. Local anaesthetic activity ate to these routes.

Thus, for example, they can be presented in the form of tablets, capsules, gelules, suppositories and injectable solutions. It will be understood that the invention includes pharmaceutical compositions which contain one or serveral of the new derivatives.

The daily dosage can, according to the case, vary from 50 to 600 mg.

The following is an example of a pharmaceutical composition:

The citrate of the N,N-diethylamino propyl esters wherein R is selected from the group consisting of 2)3 z 5)z. H2)z 2 5)2,

or pharmaceutically acceptable acid addition salts thereof.-

2. The citric acid addition salt of the N,N- diethylamino-propyl ester of a-allyl ,B-[benzo(b)thienyl-3]propionic acid.

3. A compound according to claim 1 in the form of an oxalic acid addition salt.

4. A compound according to claim 1 in the form of a citric acid addition salt. 

1. A COMPOUND OF THE FORMULA
 2. The citric acid addition salt of the N,N-diethylamino-propyl ester of Alpha -allyl Beta -(benzo(b)thienyl-3)propionic acid.
 3. A compound according to claim 1 in the form of an oxalic acid addition salt.
 4. A compound according to claim 1 in the form of a citric acid addition salt. 